Shock-absorbing antifriction-spring.



l. Nl. HAMILTON.

SHOCK ABSORBING ANTIFRlCTION SPRING.

AP.P|.1cA.T|oN.F1LED 0m11.191s. RENEWED MA1/7.1918.

' 1,268,966..v Patented June 11, 1918.

j UNITED STATES PATENT OFFICE. 'l

JOHN M'. HAMILTON, 0F LS ANGELES, CALIFORNIA.

Specification of Letters Patent.

Patented June 11, 1918.

Application led December 11, 1916, Serial No. 136,133. Renewed May 7,.1918. Serial No. 233,170.

To all whom t may concern.'

Be it known that I, JOHN M. HAMILTQN, a A citizen of the United States,residing at Los Angeles, in the county of Los Angeles, State ofCalifornia, have invented new and useful Improvements .inShock-Absorbing Antifriction-Springs, of which the following is aspecification.

This invention relates -to improvements in vehicle springs such as areused on automobiles and the like; and the present improvement has forits object the provision of a spring equipped with shock absorbingmechanism and also, preferably in combination with the shock vabsorbingmechanism, equipped with anti-friction devices.

It is an object of this invention to provide a shock absorber whichshall be contained in, and be an integral part of, the spring itself;one which may be built with' the spring as an integral part thereof, andwhich consequently, does not need to be attachedv to the spring as anattachment or exterior auxiliary. It is also an object .of thisinvention to provide certain A' provements in antifriction devices forsprings. v

These objects, and other objects of my invention, will be understoodfrom the following detailed specilication of preferred forms of mydevice, reference being had to the accompanying drawings in which:Figure l is a plan of my improved spring, parts {being broken away forpurposes of illustration; Fig. 2 is a longitudinal section of thespring; Fig. 3 is an enlargement of a portion of Fig..2;-Fig. t is asection taken as indicated by line 4 of Fig. 3; Fig. 5 is a sectiontaken as indicated by line 5 on Fig. 3; Fig. 6 is a view taken asindicated by line 6-6 on Fig. 3; Fig. 7 is a similar view showing amodification, and Fig. 8 is a section taken as indicated by line 8 8 onFig. 7.

In the drawings I have shown a spring including the usual spring leaves10 between which I place the spring members 11. These spring members 11are preferably shorter than the leaves and extend throughout the middleportions only of the leaves, although the extent of these spring membersis not a feature to which I limit myself. The nature and action of thesespring members will be hereinafter fully described; their actionincluding not onlythat of shock absorbing, but also, 1n the frictionlesscombination, that of acting as spacers for the spring leaves. Y

' The spring leaves being spaced apart, as illustrated, I place betweentheir outer portions the rollers 12. These rollers are spaced from eachother and extend from the outer ends of the spring members 11 toapproximately the outer ends of thespring'leaves.

vThese rollers act to relieve the usual frictional Contact between therelatively moving surfaces of the outer partslof the spring leaves. Itwill be understood that the inner or ce tral parts of the spring leaveshave comp ratively little relative sliding motion, while the outer partsof the spring leaves have so much slidingmotion that usually thefriction between them damps olf the'proper resilient VVaction of thevehicle sprmg. v v

Inl Figs. 3, 4, 5 and 6 I show one method of-mounting and s'pacingtherollers 12. I attach a spacer spring member 11, the attachment being bypivotal-connection at 14 as illustrated. This spacer frame 13 ispivotally connected at 15 to the next spacer frame 16; and then Iprovide further spacer frames 16 which ex'- tend out to the ends of thespring leaves, these frames being similarly pivotally interconnected atthe points 15. The spacer frames are all made alike; and the onlydifference between the frames 13 and .the

frames 16 is that the frames 13 may be shorter than the frames 16; butthis is not necessarily the case. Each of these frames has a central web17 and side iianges 18; the whole being pressed out of one piece of-sheet metal. The rollers 12 lie concentrieally on the pivotal points 15and each spacer frame has at each end the upwardly projecting rollerengaging lips 19 and similar downwardly projecting lips 20. These lipsare bent so as to form cages for the rollers, allowing the rollers tomove rotatively without friction. It will be noted that the frames,being pivotally interconnected at the axes of the-rollers, move with thespring leaves and do not interfere with the proper operation of therollers.

In Figs. 7 and 8 I have shown a modified side and passes vthrough theroller 12, which is made hollow for this purpose, the rollers fittingmore or less loosely around. the pin and fitting vfairly loosely betweenthe opposite edges of adjacent spacer frames.

' ing application, S. N. 165,337, filed April `th, 1917, ll set'forthand claim the antifriction devices herein shown; and in this presentapplication l direct the claims to certain peculiar features of theauxiliary spring members; and also, generally, to the combination ofantifriction devices with auxiliary spring members. l preferably makeand arrange these spring members so as to act as shock absorbers; thatis, so as to prevent upward rebound of the vehicle due to the reboundingaction of .the spring. These spring members 11 are preferably made ofthe same spring steel as that of the spring leaves 10, and, as a typicalcase, are about one half as thick. The aggregate strength of theauxiliary spring members may be, and in the present vcase is preferably,less than that of the leaves; preferably the number of auxiliary membersis less than that ofthe leaves, and preferably' the individual strengthofthe members is'less than that` of a leaf. And the auxiliary springmembers are placed between those leaves that are tied together by theclips 30, so that all the auxiliary members exert downward force'effective on the uppermost leaf, to which the vehiclev body is connectedfor suspension. rlFhe spring leaves are shaped to such a normal curvedconguration as illustrated; but the auxiliary spring members 11 arepreferably straight, or substantially so; or, as compared with thecurvature ofl the spring leaves, these auxiliary spring members haveless curvature, or may be even curved somewhat oppositely to thecurvature of thespring leaves. The initial unstressed curvature of theauxiliary members depends' upon the nature of the spring, and dependsupon A the shape of the spring when normally Weighted; preferably beingof such shape as either to substantially conform to the weight.- edshape of the spring or so. curved as to eX- ert a slight downward pullon the spring when weighted. As a result, these auxiliary spring membershave (when the spring is unstressed by a load in the position shown inthe drawings in Fig. 2) a downward pulling e'ect upon the spring leaves,and have an edect to retard the upward rebound action of the springleaves. rlhe spring members 11' are under a normal, initial tension, dueto being Hexed to the normal curvature of the spring leaves. ll nd, in atypical case, thatv incense when the spring leaves are one-quarter inchthiclr, if llv malrethe auxiliary spring membersnormally straight, ofone-,eighth inch'` thiclmess, and put in three of tnem in spacesbetweenfthe leaves, thenthe rebound ab-l, And thisl lines at 10EL and11a` ll show typical initial entirely unstressed shapes of a spring lear10 and a spring member. 11. Now, when a load is put on the spring allthe superimposedspring leaves and members are moved down, to a lessercurvature than shown in Fig. 2, to a curvature approximately corre-`sponding to the curvature shown in dotted lines at 11a; so that, asherein stated, when the spring is normally weighted, the spring members11 are ,in substantially unstressed condition. r, when the spring isnormally weighted, it may not be brought down to thecurvature shown at11a; and the membersll will then be normally slightly stressed upwardlyso that they still exert some downward pull on the spring leaves.

llt will be seen that the action of the auxiliary spring members doesnot pull the spring leaves down to any great 'or appre- 'ciable extent;because ordinarily, when the weight of the vehicle is on the. spring,the

leaves are moved downwardly almost to a straight position; so that,under ordinary circumstances, the auxiliary spring members are notcalled into action. 0r, if they are in action, .they are acting somewhatto pull the springdown (to straighten it out) rather than to move it up(make it more curved).

cave, or more sharply curved) then the auxiliary spring members areimmediately called into action `and by the time the spring leaves reachtheir normal unweighted position of curvature, the auxiliary springmembers-are pulling down on the spring leaves with a force sufficient tovery greatly decrease the rebound. .'llhat is, the force exerted by theauxiliary members to stop a rebound is always increasing as the springmoves up, and even before the spring leaveshave moved to the However,when the spring has 'a tendency to move up (to become more con-` pointwhere, bybeing concaved beyond their' f normal unweighted curvature,they begin to loppose the upward movement. 1t will thus be seen that myspring is made uL of parts (leaves -and auxiliary members? one of whichis practically in normal unstrained or almost unstrained state when theother is unmovement due to release of load or rebound' of the spring isopposed more by the auxiliar spring members.

' aving described a preferred form of my invention, I claim:

1. In a leaf spring, in combination, aplu rality of curved superposedspring leaves,

and auxiliary spring members interspersed between said 4spring leaves,said spring members having a normal configuration of less curvature thanthe spring leaves.

-2. In a leaf spring, in combination, a plurality of curved superposedspring leaves, and auxiliary springmembers interspersed between saidspring leaves, said spring members having a normal configuration of lessp curvature than the spring leaves, said spring members being of lesserresilient strength than said spring leaves.

3. In a leaf spring, in combination, a plurality of curved superposedspring leaves, and auxiliary spring members interspersed between saidspring leaves, said spring members having a normal\conguration of lesscurvature'than the spring leaves, said spring 4'members being of lesserresilient stren yh than said spring leaves and extendmg throughout thecentral portions of the spring leaves.

4. In a leaf spring, in combination, a plu-- -v rality Q35 of curvedsuperposed spring leaves, iary spring members interspersed between saidspring leaves, said spring members having a normal configuration of lesscurvature than the spring leaves, said spring auxi members being oflesser resilient strength than said spring leaves and extending ithroughout the central portions of the spring l leaves, and rolling'bearings between theA outer portions of those spring leaves which arespaced apart by said auxiliary spring members. 'p

5. In a leaf spring, in combination, a plu'- ralit of curved superposedspring leaves, auxi iary spring members interspersed between said springleaves, said'spring members having a normal configuration ofv lesscurvature than the spring leaves, said spring members being of lesserresilient strength than said spring leaves and extending throughout thecentral portions of the springleaves, rollin bearings between the outerportions of tllose sprlng leaves which are spaced apart by'saidauxiliary spring members, and spacer `frames for said rolling bearingspivotally connected to put an initial stress upon said leaves, and.,

rolling bearings situated between the outerparts of said leaves whoseinner parts are paced apart by said auxiliary spring memers.

7. In a leaf spring,in combination, a4 pluralit of superposed` curvedspring leaves, auxi iary springmembers interspersed .between the centralportions of, said leaves and having a normal curvature less than that ofthe spring leaves, and rolling bearings between the outer portionsofthose spring leaves whosecentral parts are spaced apart by saidauxiliary spring members.

8. In a leaf spring, in combination, a plurality of superposed springleaves all of substantially the same unstressed shape, and

an auxiliary spring member between two of the leaves, said auxiliarymember being of suchyunstressed shape as to have a resllient v.actiontending to normally distort the spring leaves in the same direction asthat caused by the load carried by the spring.

9. In a leaf spring, in combination, a plu-- rality ofsuperposed springleaves all of substantially the same unstressed shape, and an vauxiliaryspring member between two of the spring leaves when under their normalload. n

11. In a leaf spring, in combination, a plurality of superposed springleaves, auxiliary spring members interspersed between the centralportions of the leaves, and anti-friction members situated between theouter parts of the leaves whose inner parts are ls)paced apart by theauxiliary sprlng memers.

In ywitness that I claim the foregoing I have hereunto vsubscribedmyvname this 1st day of December, 1916. p

.` A J OHN M, HAMILTON.

' Witnesses: i

JAMEs T. BARKELEW, y ELwoon II.BARKELE W.

